Since its commercial beginnings in the early 1990s, the Internet has quickly spread throughout the world and is nowadays widely used as an everyday tool in the most advanced regions.
Almost everyone is now familiar with the World Wide Web, one of the most popular services provided in the Internet, allowing the user to download and display web pages on his computer, provided that the latter is connected to the Web and equipped with a suitable software application called a web browser using the HyperText Transfer Protocol (HTTP), some of the most known being Microsoft Internet Explorer® or Mozilla Firefox®.
Basically, the user inputs the address (or activates a corresponding hyperlink), called Uniform Resource Locator (URL), of the web page he wishes to access to, like http://www.websitename.com/webpage, http://meaning that HTTP is the protocol to be used by the web browser, www.websitename.com being the name of the web server where the web page is hosted and /webpage the location of the targeted web page within the web server.
The web browser sends the request for the web page to the web server, which upon reception of the request retrieves the web page, generally under the form of a text file written in a web browser-readable language such as the HyperText Markup Language (HTML), and returns it to the web browser. The web browser then displays the web page, according to the page layout defined in the HTML file.
Most web pages include contact information such as email addresses, telephone or fax numbers, allowing the user to get information about possible correspondents he may contact in order to access further information or services. Such contact information may be presented in the form of Uniform Resource Identifiers (URIs). A URI, as defined by the Internet Engineering Task Force (IETF) in RFC3986 standard of January 2005, is a “compact sequence of characters that identifies an abstract or physical resource”.
RFC3986 provides the following examples to illustrate several URI schemes and variations in their syntax components:
ftp://ftp.is.co.za/rfc/rfc1808.txt
http://www.ietf.org/rfc/rfc2396.txt
Idap://[2001:db8::7]/c=GB?objectClass?one
mailto:John.Doe@example.com
news:comp.infosystems.www.servers.unix
tel:+1-816-555-1212
telnet://192.0.2. 16:80
urn:oasis:names:specification:docbook:dtd:xml:4.1.2
The mailto and tel URIs are peculiar with respect of other URIs, for they generally point to resources (which are generally human, although tel may point to a contact center and mailto to an automatic email system) whom the user may wish to contact directly in a peer-to-peer (P2P) communication session.
A new network architecture recently appeared, called the Internet Protocol Multimedia Subsystem (IMS), allowing the merging of data and speech within same communication sessions. IMS is based on the specification of Session Initiation Protocol (SIP) as an application layer protocol that is used for establishing, modifying and terminating multimedia sessions in an Internet Protocol (IP) network (see e.g. Poikselkä et al, The IMS, IP Multimedia Concepts and Services, Wiley, 2nd edition, 2006).
SIP is becoming the standard for establishing Voice over IP (VoIP) communication sessions. It requires that a user agent (UA) of a caller terminal (such as a computer implemented with a VoIP application) be informed of a specific URI, called SIP URI, of a recipient terminal. SIP URI, like mailto and tel URIs, is to be used in peer-to-peer communication session.
Syntax of SIP URIs is provided by IETF in RFC3261 standard of June 2002. RFC3261 provides the following example to illustrate a SIP URI:
sip:+658-555-1234567;postd=pp22@foo.com;user=phone
There is evidence that most industrial efforts are being made to facilitate the merging of voice and data in common networks. However the question of how the users will apprehend and leverage the new functionalities is still pending. It will certainly depend upon how the information will be provided and made available.
An attempt has been made for optimizing delivery and deployment of web services to consumers by providing presence information in addition to business/technical information about different web service providers to the consumers so they can select a web service provider: see US patent application No. 2007/0083627 (Mohammed).
Another attempt has been made for enhancing customer assistance to Internet users, whereby a web server provides content to a web site, which includes presence information provided by an enterprise server, allowing online users to see in the current availability of real time customer support, see e.g. US patent application No. US 2005/0114159 (Ozugur).
Although these attempts enhance web services, they require important modifications of the network architecture on the server side, thereby preventing the new functionalities to be extended to any kind of web service on the client side.